UV, IR, broadband, and ultrafast lasers are essential to an enormous range of applications from spectroscopy to micromachining to laser surgery. However, it is more difficult to find beam shaping optics such as beam expanders for these non-visible lasers, as conventional transmissive optics are highly wavelength dependent and can suffer from dispersion. Reflective beam shaping optics solve these issues with a broadband achromatic design by completely eliminating chromatic and spherical aberration. Here you find 2 examples of relevant beam shaping optics:
Reflective Beam Expanders are modified Gregorian or Cassegrain mirror systems that offer broadband performance virtually free of chromatic and spherical aberration. They are compatible with a wide range of laser sources including:
A convex mirror is used to expand an incident beam onto a concave mirror, resulting in a larger collimated beam.
You can learn more here.